Illuminated tubular lighting of the neon tube type is well known and has been employed for many years in advertising display signs and other decorative lighting. Typically, such neon signs are constructed of a support frame on which may be mounted a back display panel and variously contoured or configured neon illuminating glass tubing. The glass tubing is generally supported in spaced relation from the support frame and back panel by a plurality of short, stand-off elements attached to and extend outwardly from the sign frame at spaced locations along its length. Generally, the tubing is secured to the support elements by a wire tie, or certain of the elements are constructed with a C-shaped clamp portion which engages and retains the tubing. Generally, the stand-off supports are attached to the sign support frame or the back panel by welding, rivots, or threaded fastening elements, such as screws or bolts, received in suitable openings in the back panel or frame.
It has also been known to provide spring members in the tube supports between the support frame and the tube itself to provide a force-dampening effect to protect against tube breakage in shipping and handling of the signs, and to provide a degree of lengthwise adjustment of the support elements to accomodate for uneveness in tubing and/or support frame dimensions and separation distances.
Since the luminous tubing of neon display signs is variously shaped, curved, and bent to provide desired lettering or other special artistic configurations in the sign, it is desirable to provide a degree of adjustability of the tube support elements to position them in the proper location and spacing on the sign frame to correctly support the tubing thereon. A number of luminous tube support constructions for mounting tubing on supporting surfaces are disclosed in the following U.S. Pat. Nos.: 1,822,980 Palmer, 2,545,416 Staaf, 2,629,814 Brown, 2,885,538 Mahon et al., 3,135,488 Leonard, 4,201,004 Witt.